The Study of Momentum, Mass, and Heat Transfer in a Droplet-Laden Turbulent Airflow Over a Waved Water Surface by Direct Numerical Simulation
The Study of Momentum, Mass, and Heat Transfer in a Droplet-Laden Turbulent Airflow Over a Waved Water Surface by Direct Numerical Simulation
复制标题
DOI：
10.1029/2018jc014346
复制
发表时间：
2018-11-01
影响因子：
3.6
通讯作者：
Zilitinkevich, S. S.
中科院分区：
文献类型：
--
作者：
Druzhinin, O. A.;Troitskaya, Yu. I.;Zilitinkevich, S. S.
本文采用直接数值模拟（DNS）方法研究了波浪形水面上含液滴气流的湍流交换过程。在DNS中，湍流Couette流被认为是海洋大气表面层中恒定通量层的模型。在水面的二维驻波规定，并假定不受气流和/或液滴。将不同大小的蒸发液滴以水的初始速度和温度喷射到波峰附近的空气中，从而模仿海绵喷雾液滴。的气流速度，温度和湿度的演化方程求解的欧拉框架中，同时跟踪在拉格朗日框架中的单个液滴的坐标和速度，温度和质量的方程。从液滴到空气的动量（Q（m））和感热（Q（S））和潜热（Q（L））热通量被评估为相位平均欧拉场和沿着拉格朗日液滴轨迹随时间积分的通量。结果表明，液滴从周围空气中提取动量（Q（m）0），并随着液滴直径d的增加而增加，而对于直径d的液滴，Q（S）0为零
This paper investigates turbulent exchange processes in a droplet-laden air flow over a waved water surface by performing direct numerical simulation (DNS). Turbulent Couette flow is considered in DNS as a model of a constant-flux layer in the marine atmospheric surface layer. Two-dimensional stationary waves at the water surface are prescribed and assumed to be unaffected by the airflow and/or droplets. Evaporating droplets of different sizes are injected into the air in the vicinity of wave crests with initial velocities and temperatures of water, and thus mimicking spume sea-spray droplets. Evolution equations of the airflow velocity, temperature, and humidity are solved in a Eulerian framework simultaneously with the equations of individual droplets coordinates and velocities, temperatures, and masses tracked in a Lagrangian framework. The momentum (Q(m)) and sensible (Q(S)) and latent (Q(L)) heat fluxes from the droplets to air are evaluated both as phase-averaged Eulerian fields and as fluxes integrated over time along Lagrangian droplets trajectories. The results show that droplets extract momentum from the surrounding air (Q(m)0 and increases with droplet diameter, d, whereas Q(S)0 vanishes for droplets with diameters d